OpenAI Has a Free API Tier — Build ChatGPT Apps, Generate Images, and Use GPT-4o Mini Without Breaking the Bank

OpenAI gives every new developer $5 in free credits — enough for thousands of API calls with GPT-4o mini. You can build chatbots, generate images with DALL-E, transcribe audio with Whisper, and create embeddings for search. All through a simple REST API. Here's how to start building with it. Get Your Free API Key Sign up at platform.openai.com Go to API keys → "Create new secret key" Copy your key (starts with sk- ) New accounts get $5 free credit (expires after 3 months) 1. Chat Completion (GPT-4o Mini) curl https://api.openai.com/v1/chat/completions \ -H "Authorization: Bearer sk-YOUR_KEY" \ -H "Content-Type: application/json" \ -d '{ "model": "gpt-4o-mini", "messages": [ {"role": "system", "content": "You are a helpful coding assistant."}, {"role": "user", "content": "Write a Python function to check if a number is prime."} ] }' GPT-4o mini costs $0.15 per million input tokens — your $5 credit = ~33 million tokens. 2. Generate Images (DALL-E 3) curl https://api.openai.com/v1/images/